1. Field of the Invention
This invention relates generally to the field of equipment and methods of installation thereof of subsea wellhead equipment. In particular, the invention concerns a ROV deployed cap for a Xmas tree for a subsea well and the method of installing and retrieving the tree cap.
2. Background and Objects of the Invention
Prior tree caps have been installed by using a drill pipe connector arrangement. Prior tree cap design has been elaborate, almost a piece of art. Extensive machining and weight issues became the norm. An extra trip of the drill pipe was required simply to retrieve or lower the tree cap. As the offshore oil industry moves to deeper and deeper depths, the time that it takes to lower or retrieve the tree cap with drill pipe will cost a well operator thousands of dollars in rig time alone.
Accordingly, a primary object of the invention is to provide a light weight ROV installable tree cap for a subsea Xmas tree.
Another object is to provide a method of installing and retrieving the tree cap by using pressure fluid apparatus for stabbing the cap in place on the production hub and for retrieving the cap.